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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 5 |
| 3 | 10 |
| 4 | 18 |
| 5 | 35 |
| 6 | 74 |
| 7 | 154 |
| 8 | 317 |
| 9 | 658 |
| 10 | 1370 |
| 11 | 2851 |
| 12 | 5930 |
| 13 | 12338 |
| 14 | 25677 |
| 15 | 53434 |
| 16 | 111194 |
| 17 | 231395 |
| 18 | 481538 |
| 19 | 1002090 |
| 20 | 2085365 |
| 21 | 4339682 |
| 22 | 9030962 |
| 23 | 18793603 |
| 24 | 39109842 |
| 25 | 81388322 |
| 26 | 169370645 |
| 27 | 352463530 |
| 28 | 733483298 |
| 29 | 1526392675 |
| 30 | 3176452154 |
| 31 | 6610257274 |
[2,5,10,18,35,74,154,317,658,1370,2851,5930,12338, 25677,53434,111194,231395,481538,1002090,2085365, 4339682,9030962,18793603,39109842,81388322, 169370645,352463530,733483298,1526392675, 3176452154,6610257274] |